Download Important New Update to the Prescribing Information for

Important New Update to the
Prescribing Information for
SYNTHROID® (levothyroxine sodium) tablets, for oral use
In February 2017, SYNTHROID Prescribing Information was changed to a new format.
The following describes several of the changes in the SYNTHROID Prescribing Information, in addition to
the format change:

The indication for use section was updated and reworded

Proton Pump Inhibitors (medicine that reduces the production of acid in the stomach) were added as a medicine
that can cause your body to absorb less levothyroxine and reduce its effect

Tyrosine Kinase Inhibitors (medicine that is used for some thyroid cancers) were added as a medicine that can
cause hypothyroidism

Grapefruit juice was added as a food that may cause your body to absorb less levothyroxine and may reduce its
effect

A statement was added that atrial fibrillation (irregular, often rapid heart rate) is a common side effect seen in
elderly patients taking levothyroxine

A statement was added that seizures occurred in a 3-year-old child who swallowed an overdosage (3.6 mg) of
levothyroxine

Information was updated to explain that taking too much levothyroxine may cause decreased bone strength,
especially in women after menopause.
This is not a complete list of all the changes made to the Prescribing Information for SYNTHROID.
Please refer to the full Prescribing Information for more details.
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch or call
1-800-FDA-1088 (1-800-332-1088).
If you cannot afford your medication, contact www.pparx.org for assistance.
Click here for SYNTHROID full Prescribing Information.
Click here for Use and Important Safety Information for SYNTHROID.
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Please see Use and Important Safety Information on page 2.
Click here for full Prescribing Information for Synthroid.
Use
SYNTHROID® (levothyroxine sodium) tablets, for oral use is a prescription, man-made thyroid hormone that
is used to treat a condition called hypothyroidism. It is meant to replace a hormone that is usually made by your thyroid
gland. Generally, thyroid replacement treatment is to be taken for life. SYNTHROID should not be used
to treat noncancerous growths or enlargement of the thyroid in patients with normal iodine levels, or in cases of temporary
hypothyroidism caused by inflammation of the thyroid gland (thyroiditis).
Important Safety Information

Thyroid hormones, including SYNTHROID, should not be used either alone or in combination
with other drugs for the treatment of obesity or weight loss. In patients with normal thyroid levels,
doses of SYNTHROID used daily for hormone replacement are not helpful for weight loss.
Larger doses may result in serious or even life-threatening events, especially when used in combination with
certain other drugs used to reduce appetite.

Do not use SYNTHROID if you have uncorrected adrenal problems.

Taking too much levothyroxine has been associated with increased bone loss, especially in women
after menopause.

Once your doctor has found your specific SYNTHROID dose, it is important to have lab tests done,
as ordered by your doctor, at least once a year.

Foods like soybean flour, cottonseed meal, walnuts, and dietary fiber may cause your body to absorb less
SYNTHROID from the gastrointestinal tract. Grapefruit juice may cause your body to absorb less levothyroxine
and may reduce its effect. Let your doctor know if you eat these foods, as your dose of SYNTHROID may need
to be adjusted.

Use SYNTHROID only as ordered by your doctor. Take SYNTHROID as a single dose, preferably on an empty
stomach, one-half to one hour before breakfast.

Products such as iron and calcium supplements and antacids can lower your body’s ability to absorb levothyroxine, so
SYNTHROID should be taken 4 hours before or after taking these products.

Tell your doctor if you are pregnant or breastfeeding or are thinking of becoming pregnant while taking SYNTHROID.
Your dose of SYNTHROID may need to be increased during your pregnancy.

It may take several weeks before you notice an improvement in your symptoms.

Tell your doctor if you are taking any other drugs, including prescription and over-the-counter products.

Tell your doctor about any other medical conditions you may have, especially heart disease, diabetes, blood clotting
problems, and adrenal or pituitary gland problems. The dose of other drugs you may be taking to control these
conditions may have to be changed while you are taking SYNTHROID. If you have diabetes, check your blood sugar
levels and/or the glucose in your urine, as ordered by your doctor, and immediately tell your doctor if there are any
changes. If you are taking blood thinners, your blood clotting status should be checked often.

Tell your doctor or dentist that you are taking SYNTHROID before any surgery.

Tell your doctor if you develop any of the following symptoms: rapid or abnormal heartbeat, chest pain, difficulty
catching your breath, leg cramps, headache, nervousness, irritability, sleeplessness, shaking, change in appetite,
weight gain or loss, vomiting, diarrhea, increased sweating, difficulty tolerating heat, fever, changes in menstrual
periods, swollen red bumps on the skin (hives) or skin rash, or any other unusual medical event.

Partial hair loss may occur during the first few months you are taking SYNTHROID.
This is the most important safety information you should know about SYNTHROID. For more information, talk
with your doctor.
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Click here for full Prescribing Information for Synthroid.
Reference: 1. SYNTHROID [package insert].
©2017 AbbVie Inc. North Chicago, IL 60064 605-1893121 February 2017 Printed in U.S.A.